CD11a heterozygous knockout T cells fail to induce asymmetric LFA-1 expression and disparate migration patterns in first-division CD8⁺ T cells. (A) Representative flow cytometry of surface (CD11a Ab) and total (mYFP) LFA-1 expression levels from CD11a-mYFP/OT-I Het and WT OT-I naive CD8⁺ T cells; n = 3 mice. (B) Quantification of relative fluorescence intensity of mYFP from CD11a-mYFP/OTI (WT) versus CD11a-mYFP/OT-I Het CD8⁺ T cells at the contact site with Ag-bearing APCs (N4 or D7). Data are expressed as mean of total 25–40 cells. (C) Representative flow cytometry analysis of asymmetric expression of CD11a-mYFP in WT (CD11a-mYFP/OT-I) versus LFA-1 Het (CD11a^+/−-mYFP/OT-I) CD8⁺ T cell division from x31-OVA–infected mice 56 hpi; n = 6 mice. (D) Frequency distribution of migration indices measured from CD11a-mYFP (WT Div1) and CD11a-mYFP^+/− (Het Div1) first-division or CD11a-mYFP^+/− (Het Undiv) undivided CD8⁺ T cells. Data collected from three independent experiments (one mouse per experiment; 45–60 cells/mouse) were fit to nonlinear regression and multimodality was assessed with the Kolmogorov–Smirnov test. Asterisk indicates significance between WT Div1 and Het Div1 (*, P < 0.01). (E) Number of tissue-resident memory (TRM; CD103⁺ [integrin α_E], CD62L^low [L-selectin], CD44^high), central memory (TCM; CD62L⁺, CD44^high), and effector memory (TEM; CD62L^neg, CD44^high) CD11a-mYFP⁺ CD8⁺ T cells found in the draining lymph node and lung 60 dpi (CD11a^+/−-mYFP/OT-I T cells: Het, CD11a-mYFP/OT-I/Rab27 KO T cells: Rab27KO). Data represent mean ± SEM; n = 4 mice/group. *, P < 0.05.